why? Juan is richer than stewart by about 9 fold, if this goes wrong he has more to lose. Tony left a great, and higher paid, job at Tottenham with a strong reputation, if this goes wrong he won't ever get to be an MD again and probably couldnt just walk into a club as good as Spurs and get a job with that seniority. If either of those guys thought stewart was incompetent or a fraud, they wouldnt want to risk their reputations, or in Juan's case, money, with him.
Styewart is the largest shareholder, he runs the thing, they are happy for him to do that, thats quite the vote of confidence.